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Subject: Re: CONFIG_DEBUG_PAGEALLOC generates WARN_ON() in ppc32 hash
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Kumar Gala <galak@kernel.crashing.org>
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Date: Sat, 28 Mar 2009 10:05:57 +1100
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On Fri, 2009-03-27 at 06:56 -0500, Kumar Gala wrote:
> Ben,
> 
> If we have CONFIG_DEBUG_PAGEALLOC enabled we end up hitting the  
> WARN_ON() in set_pte_at() when we boot.  This appears because we've  
> already setup pte's via mapin_ram() after which we end up calling  
> kernel_map_pages().
> 
> So I'm not sure if __change_page_attr() should be doing something  
> different or if the WARN_ON() should be conditional on ! 
> CONFIG_DEBUG_PAGEALLOC

Or use __set_pte_at() ?

Note that C_D_P doesn't work on hash32 anyway...

Ben.